(a) Field of the Invention
The invention described herein relates to novel compounds classified in the field of organic chemistry as methanes, useful as color-forming substances, particularly in the art of transfer imaging, pressure-sensitive and thermal responsive carbonless duplicating and electrochromic recording to transfer imaging systems containing said compounds; to pressure-sensitive and thermal responsive carbonless duplicating systems containing said compounds; to electrochromic recording systems containing said compounds; and to a process for preparing said methanes.
(b) Information Disclosure Statement
Several classes of organic compounds of widely diverse structural types are known to be useful as colorless precursors for transfer imaging systems. Among the more important classes, there may be named leuco-type dyestuffs such as- phthalides, for example, crystal violet lactone, Malachite green lactone; fluoran, for example, 3-dialkylamino fluoran, 3-dimethylamino-6-methoxyfluoran; phenothiazines, for example, benzoyl leuco methylene blue; Rhodamines, for example, 3-methyl-spiro-dinaphthopyran. The classes of organic compounds listed above also generally find utility in pressure-sensitive and thermal responsive carbonless duplicating systems.
Typical of the transfer imaging systems is the system described in U.S. Pat. No. 4,399,209 which issued Aug. 16, 1983. In this patent a transfer imaging system is disclosed wherein images are formed by image-wise exposing a layer comprising a chromogenic material and pressure rupturable containing as an internal phase, a photosensitive composition. In this system the chromogenic material is encapsulated with the photosensitive compound. Upon exposure to filtered U.V. or blue light in the wavelength range of 380 to 480 nonometer a certain portion of the capsules will harden. The capsules in which the internal phase has remained liquid are ruptured and the chromogenic material is image-wise transferred to a developer or copy sheet where the chromogenic material reacts with a developer to form an image.
Typical of the many commercially accepted pressure-sensitive and thermal-responsive carbonless copy systems are those described in U.S. Pat. Nos. 2,712,507; 2,800,457; 3,041,289; and 4,000,087, which issued July 5, 1955; July 23, 1957; June 26, 1962; and Dec. 28, respectively.
Several classes of organic compounds of widely diverse structural types are known to be useful as colorless precursors for electrochromic recording. Among the more important classes, there may be named leuco-type dyestuffs such as: phthalides, for examples, crystal violet lactone, Malachite green lactone; fluorans, for example, 3-diethylamino-5,7-dimethylfluoran; and indolinobenzospiropyrans, for example, 1,3,3-trimethyl-6-chloro-8'-methoxyindolinobenzospiropyrans. Also utilized as colorless precursors for electrochromic recording, either alone or in admixture with the leuco compounds indicated above, are substances known as redox indicators. The redox indicator which becomes colored in situ in the electrochromic recording process also is generally a leuco compound. Among the type of compounds which are applicable as redox indicators are phenothiazines, for examples, leuco methylene blue and benzoyl leuco methylene blue. Other specific indicators are Leucoethyl Nile Blue, Leucomethyl Capyrl Blue and Leucosafranine T. Typical of the many such electrochromic recording systems taught in the prior art as those described in U.S. Pat. Nos. 3,726,769, 3,871,972, 3,864,684, 4,017,366, 4,133,933, and Re. 29,427 which issued on Apr. 10, 1973, Mar. 18, 1975, Feb. 4, 1975, Apr. 12, 1977, Jan. 9, 1979, and Oct. 4, 1977, respectively. The methods for electrochromic recording taught in the prior art have many variations. Basically, a sheet of paper is coated or treated on one or both sides with a coating formulation containing at least one colorless color-forming (leuco) compound. Electrical current in the selectively applied to the coated side of the paper by some means, for example, a stylus or a printing head to which an electrical potential can be applied. The application of the current causes any electrochromic reaction involving the leuco compound to produce a visible image corresponding to the design traced by the stylus or that of the printing head.
Many of the color formers in the prior art suffer one or more disadvantages such as low tinctorial strength, low resistance to sublimation, low susceptibility to copiability of the color-developed images in standard office copying machines, for example, a xerographic type of copier, poor image stability in the pressure of light, i.e., the product image fades losing intensity or changes to a less acceptable color, and low solubility in common organic solvents. The latter disadvantage requires the use of specialized and expensive solvents in order to obtain microencapsulated solutions of sufficient concentration for use in pressure-sensitive copying systems and transfer imaging systems.
There are no items to date appear to constitute relevant prior art with regard to the instant invention.